Objective: To increase knowledge of moderating influences on alcohol use, specifically, religious-spiritual (R/S) dimensions and underlying genetic and environmental effects on R/S moderation of alcohol onset and progression. Guided by current etiological models, analyses will also examine R/S effects on the hypothesized mediators of genetic risk for alcohol use disorders: behavioral undercontrol and negative affect regulation. Aims: (1) characterization of R/S dimensionality and R/S-alcohol use association;(2) characterization, using full phenotypic models, of main and interactive effects of R/S dimensions on early onset and heavy alcohol use;(3) estimation of genetic, shared, and non-shared environmental contributions to the variance and covariance of R/S dimensions and to their correlations with age-at-onset of alcohol use and heaviness of alcohol use;(4) to test the role of R/S dimensions in moderating genetic or shared environmental effects on age-at-onset of alcohol use and heaviness of alcohol use, and to characterize moderating (genotype x environment) effects. Method: Secondary data analyses will be conducted on existing, deidentified data from a large-scale prospective research study of substance use onset and progression and associated psychiatric disorders from previous assessments of Missouri-born adolescent female twins and their families. Available R/S variables will permit examination of the moderating effects of five R/S dimensions within two key models of alcoholism etiology. Relevance: Resultant findings will be of considerable importance to (a) etiological efforts in characterizing the mediators and moderators of alcoholism risk, and to (b) treatment and prevention efforts that have frequently observed treatment enhancing and protective effects of R/S on alcoholism outcomes.